Field of the Invention
This invention relates to instruments used during surgical procedures for securing a bone tendon bone graft inside bone tunnel. More particularly, this invention relates to bone clamping instruments for trimming the bone tendon portion of a graft for a replacement anterior cruciate ligament (ACL) or other tendon/ligament.
Description of the Background Art
Presently there exist many surgical techniques employed for replacing, reconstructing or securing synthetic or biological connective tissues to bone surfaces, such as attaching and maintaining an anterior cruciate ligament (ACL) within a knee. More recent surgical procedures for tendon replacement and reconstruction involve auto-grafting a tendon to the site of a torn or dislocated tendon. Early surgical procedures involved stapling the auto-grafted tendon into placement.
More particularly, reconstruction is the standard of care after an ACL injury. In surgery it is generally known to use an autograft taken from the knee of the patient to replace the ruptured ACL. The two most commonly used are the bone-patellar tendon bone (BPTB) and the hamstring tendon (semitendinosus tendon with or without gracilis tendon). Allografts, synthetic grafts and quadriceps tendon grafts have also been used as ACL substitutes. The surgical techniques of the ACL reconstruction using bone-tendon bone (BTB) graft and hamstring tendon graft are described in detail in the following references: Beck, C. L., Jr.; Paulos, L. E.; Rosenberg, T. D.: “Anterior cruciate ligament reconstruction with the endoscopic technique,” Operative Techniques in Orthopaedics, 2:96-98, 1992; Stahelin, A. C.; Weiler, A.: “All-inside anterior cruciate ligament reconstruction using semitendinosus tendon and soft threaded biodegradable interference screw fixation,” Arthroscopy, 13:773-779, 1997; Fu, F. H.; Ma, C. B.: “Anterior Cruciate Ligament Reconstruction Using Quadruple Hamstring. Operative Techniques,” Orthopaedics, 9:264-272, 1999. Additional references of interest include Hoffman, R. F. G.; Peine, R; Bail, H. J.; Sudkamp, N. P.; Weiler, A.: “Initial fixation strength of modified patellar tendon grafts for anatomic fixation in anterior cruciate ligament reconstruction,” Arthroscopy, 15:392-399, 1999. The disclosures of each of the above references are hereby incorporated by reference herein.
More specifically, among the currently available soft tissue (hamstring) graft fixation implants, currently the most commonly used method to secure an ACL substitute to a bony drill-hole in an ACL reconstruction, is the interference technique. In the interference technique, an interference screw is inserted into the space between the drill-hole and the bone tendon portion of the graft to lock it into the drill-hole. The fixation screws, like interference screws, are normally made of metal, like stainless steel or titanium or of a bioabsorbable polymer, like polylactide.
For example, as taught by U.S. Pat. No. 5,397,356, one technique for securing a replacement tendon to a bone involves harvesting a tendon having a bony section or plug at one or both ends. The tendon is threaded into a drilled hole by a guide pin or K-wire and then the bone plug is secured into position by a specially-adapted threaded pin. Importantly, the threaded pin securing the replacement tendon engages through its bony plug to secure it into position within the hole whereupon, over time, the bony plug is grafted into the knee, thereby permanently securing the replacement tendon into position.
It is important to trim the bone tendon portion of the graft to properly fit inside the bony drill-hole. Unfortunately, prior art techniques have involved trimming the bone tendon portion with a bone saw by hand without the aid of an instrument and possibly resulting in incorrect sizing of the bone tendon portion either too large or too small to properly fit into the boney drill hole.
An object of this invention is to provide a bone clamping instrument for clamping the bone tendon portion of the graft during an ACL procedure allowing the surgeon to properly trim the bone tendon portion of the graft with a bone saw to precise dimensions to properly fit into the hole.
The foregoing has outlined some of the pertinent objects of the invention. These objects should be construed to be merely illustrative of some of the more prominent features and applications of the intended invention. Many other beneficial results can be attained by applying the disclosed invention in a different manner or modifying the invention within the scope of the disclosure. Accordingly, other objects and a fuller understanding of the invention may be had by referring to the summary of the invention and the detailed description of the preferred embodiment in addition to the scope of the invention defined by the claims taken in conjunction with the accompanying drawings.